Abstract:Aim To investigate the effects of the Lobelia Chinensis Lour Alkaloids(LCLA)on endothelin-1(ET-1)mRNA expression and endothelin synthesis and release in renal hypertensive rats(RHR).Methods The glodblatt renovascular hypertension model was induced in rats by two-kidney one clip method.After 4 weeks the rats were divided into 3 groups,including the hypertensive group,the captopril group and the LCLA group,while the control group was given sham-operation.Using in situ hybridization to observe ET-1 mRNA expression in peripheral blood leucocytes.Using immunohistochemical technique to count positive rate of ET in “en face” preparations of arterial endothelium to reflect the synthesis of ET.Using radioimmunoassay to examine the level of ET in serum.Results Compared with the sham operation group,the positive rate of ET-1 mRNA in peripheral blood leucocytes(34.64%±8.39% vs 9.34%±4.47%,p<0.05),the positive rate of ET in arterial endothelium(7.42%±0.24% vs 1.58%±0.24%,p<0.05)and the plasma concentration of ET(221±24 ng/L vs 138±19 ng/L,p<0.05)were increased significantly in hypertensive rats.After treating with LCLA for 8 w,compared with the hypertensive group,ET-1 mRNA expression(20.38%±11.31% vs 34.64%±8.39%,p<0.05),endothelin(ET)synthesis(3.53%±0.21% vs 7.42%±0.24%,p<0.05)and release(191±21 ng/L vs 221±24 ng/L,p<0.05)were significantly inhibited.Conclusions The expression of ET was increased in RHR.The LCLA can inhibit the expression of ET in the transcriptional and translational level which may be effective to the preventing and treatment of the renal hypertension.

Abstract:Aim To investigate the effect and signal transduction pathway of UrotensinⅡ (UⅡ) on endothelin-1 (ET-1) production in cultured aortic tissues of rat. Methods Aortic slices were incubated with different concentration of UⅡ(10-10～10-7 mol/L) for 3 or 6 h. ET-1 both in medium and tissues were measured with radioimmunoassay. Different inhibitors were added to the medium to study the role of different signal transduction pathways in the stimulating effect of UⅡon production of ET-1. Results The study showed that UⅡ significantly stimulated ET-1 secretion (ET-1 in medium) and production (ET-1 both in medium and tissues) from rat aortic tissues, in a time and concentration dependent manner. After incubation for 3 h, ET-1 secretion and production were increased by 146% and 87.9% respectively in 10-8mol/L of UⅡ group than the control group. After incubation for 6h, ET-1 secretion was increased by 59.2%, 108%, 159.6% and 178.0% in UⅡ (10-10, 10-9, 10-8, 10-7 mol/L) group respectively. And ET-1 production was increased by 40.6%, 68.4%, 103.1% and 105.7% in 10-10～10-7 mol/L of UⅡ group respectively. Furthermore, the effect of UⅡ (10-8 mol/L) were inhibited by 34.1%, 24.5%, 32.2%, 32.1% and 27.6% (p<0.01) in secretion and by 33.5%, 31.5%, 25.8%, 28.0% and 36.8% (p<0.01) in production when incubated with nicardipine, H7, PD98059, actinomycin D and cyclophosphamide respectively, which are inhibitors of calcium channel, PKC, MAPK, mRNA production and protein synthesis respectively. Conclusion UⅡ could stimulate ET-1 synthesis and secretion in rat aortic tissues, and this effect might be mediated by Ca2+, PKC, and MAPK signal transduction pathway. It was also proposed that UⅡ might play vasoconstrictive actions partly through ET-1 production.

Abstract:Aim To investigate the relationships between plasma calcitonin generelated peptide (CGRP) and the severity of coronary lesions and left ventricular function in patients with coronary heart disease. Methods In 42 patients with fixed stenosis coronary artery ≥70% of luminal diameter in the major coronary arteries and 15 normal persons, the concentration of plasma CGRP was measured using radioimmunoassay (RIA). The relationships between plasma CGRP and the Leaman coronary artery score as well as left ventricular ejection fraction (LVEF) were assessed. Results The concentration of plasma CGRP was obviously lower in the coronary disease group than in the control group (276.12±164.75 ng/L vs 411.44±110.32 ng/L,P<0.01). The concentration of plasma CGRP was negatively related to the Leaman score (r=-0.61,P<0.001) and positively to LVEF (r=0.57,P<0.001). The Leaman score had no significant correlation to LVEF in the whole group. However, in the subgroup with the level of plasma CGRP<250 ng/L, the Leaman score had significantly negative correlation to LVEF (r=-0.49,P<0.05). Conclusions The plasma CGRP had correlation to both the severity of coronary lesions and left ventricular function in patients with coronary heart disease. In the patients with decreased concentration of plasma CGRP, the left ventricular function deteriorated with the progress of coronary lesions.

Abstract:Aim Study on the accurence and regluar patterns of atrial natriuretic factor (ANF) in the human heart befor birth. Methods Collection of 65 embryo cares from accidental abortionsor miscarriages or induced labour of the pregrant women with no cardiovascular disease in clinical diaynosio, measurement of the amount of ANF in different locations of the embryocal heart means of radioimmunoassay. Results ANF in the atria appeared in the sixth week ,but in a minute amount, increasing with the growth of the embryo, while the amount of ANF in the ventricals reached a rather higher level in the sixth week, decreasing with the growth of the embryo and then nearly disappeared after a full term. In the right auriclua of the embryos at the same age ANF reached the maximam, with the amount in the right atrium over that in the left, and the amount in the left ventricle over that in the right. Conclusions ANF in the human embryocal atria appeared in the sixth week, increasing with the growth of the embryo while ANF was also found in the ventricles and the interventricular septa, decreasing with the growth of the embryo.